Flue expander and beader.



J. L. DIDIER.

FLUE EXPANDER AND HEADER.

Patented Nov. 23,1909.

APPLICATION FILED MAR. 22, 1909.

9&1,1 90.

JOSEPH L. DIDIER, OF KNOXVILLE, TENNESSEE.

FLUE EXPANDER AND BEADER.

Specification of Letters latent.

Patented Nov. 23, 1909.

Application filed. March 22, 1909. Serial No. 485,099.

To all whom it may concern:

Be it known that I, JOSEPH L. DIDIER, a citizen of the United States, residing at Knoxville, in the county of Knox and State of Tennessee, have invented a new and useful Improvement in Flue Expanders and Beaders, of which the following is a specification, reference being had to the accompanying drawing.

My improvement relates particularly to devices or tools for expanding and beading the ends'of boiler tubes.

The object of the invention is to produce a tool which is simple and economical as to construction, and which is adapted to perform its work by the application of a minimum of power and to perform the functions of expanding and beading simultaneously, thus effecting economy in time and labor.

In the accompanying drawings, Figure 1 is a sectional elevation of a tool embodying my improvement; Fig. 2 is a section on the line 22 of Fig. 1, looking toward the left; Fig. 3 is a diagrammatic view illustrating the direction of the axes of the expanding rolls.

Referring to said drawings, 1 is a mandrel which has at one end a polygonal portion, 2, adapted for engagement with a handle or a shaft for imparting rotation to said mandrel. From this portion, 2, to its opposite end, said mandrel is straight, circular in cross-section, and tapering to approximately the extent shown by the drawings. For convenience in description, the smaller end of the mandrel will be herein termed the forward end.

-A hollow body, 3, which is analogous to a hub, loosely surrounds the mandrel, its interior diameter being a little more than the largest diameter of the tapering portion of the mandrel, so that said body can be moved lengthwise over the entire tapering portion of the mandrel. The forward end of said body is cylindrical and has three straight, elongated slots, 4, which are equi-distant from each other and the middle longitudinal plane of each of which extends diagonally across the axis of said body. But the smaller angles between said planes and said axis are so small as to almost make said axis and the intersections of saidplanes coincide. The outer portion of each of said slots is slightly contracted for the purpose of retaining the expansion rollers next described. In each of said slots rests a cylindrical expansion roller, 5, which is of proper diameter to enter one of the slots from the interior of the body, 3, and project a little way (far enough to bear against the inner face of the boiler tube) through the slightly contracted outer portion of said slot, the contraction in said slot preventing the roller from passing entirely through said slot. Thus said slots form bearings in which said rollers may rotate when the mandrel is pressed against said rollers and rotated. Said slots being set slightly oblique to the axis of the body, 3, it follows that each expansion roller, 5, may bear with its perimeter against the face of the mandrel so as to bring the axis of said roller into a plane which is parallel to the adjacent face of the mandrel and also into a plane which is perpendicular to said plane and extend diagonally across the axis of the mandrel. Such diagonal plane is represented by the dotted line, cZcZ, in Fig. 3, while the line, mm, represents the axis of the mandrel (or the body, 3), and the dotted line, pp, Fig. 1, illustrates the position of the first of said two planes. The purpose of thus placing said expansion rollers obliquely will be hereinafter explained.

Rearward of the slots, 4L, and rollers, 5, the body, 3, has an outward extension, 6, and on the outer portion of said extension is a forward-directed rim, 7, inclosing an annular space, S, in which are placed beading rollers, 9, on axles,.10, which are radial to the axis of the body, 3. Each axle has one end resting in an aperture, 11, in the rim while the other end rests in an aperture, 12, in the portion of the body adjacent one of the slots, 4. The axles, 10, are preferably set nonrotatably, while the rollers, 9, are free to turn upon said axles. Said beading rollers are tapering, the larger end being toward the axis of the body, 3, and in position to bear against the end of the tube before it has been beaded.

A curved stop plate, 13, lies against the outer face of the rim, 7, and the outer end of each axle, 10, to keep the latter in position. A screw, 14, extends through each of said plates and into said rim to removably secure said plates.

The operation is as follows: A tube being in position in the flue sheet with a sufficient length projecting through said sheet to permit beading, the forward portion of the body, 3, is pushed into the tube until the beading rollers bear against the end of the flue, the expansion rollers and the mandrel having been previously put into place in said body. Thus the expansion rollers bear outward against the tube and the inner larger portions of the beading rollers bear against the end of the tube. Since these portions of the beading rollers are tapering, they present oblique faces against the end of the tube from within the latter and cause a diagonal outward pressure when the body, 3, is drawn forward. Said body is drawn forward by the slightly spiral forward travel of the expansion rollers upon the inner face of the boiler tube when the mandrel is rotated. During such rotation, the three expansion rollers roll idly between the mandrel and the inner face of the tube, just as anti-friction roller bearings roll idly in the space between the axle and the hub. If said expansion rollers were in planes in which the axis of the mandrel lies (so that the axes of said rollers would not be diagonal to the mandrel axis) said rollers would travel in paths strictly transverse to the tube axis; but since said rollers are, as described, slightly oblique to the mandrel axis the paths of said rollers will be slightly spiral, the direction depending upon the direction of rotation of the mandrel. In practice, the expansion rollers are so set as to cause a spiral forward movement when the mandrel is rotated clockwise, while a rearward spiral movement results when the mandrel is rotated in the reverse direction. This forward creeping of said rollers and said body causes the wedging of said rollers between the mandrel and the inner face of the tube, whereby the tube is gradually expanded, and at the same time the beading rollers are made to travel under forward pressure against the end of the tube, the body, 3, being rotated and carried forcibly forward by the spiral travel of the expansion rollers.

During the first portion of the travel of the beading rollers upon the end of the tube, the edge of the latter is pressed outward, and thus the engagement between said end and said rollers is gradually shifted toward the outer ends of said rollers, whereby the working face of each of said rollers is gradually changed from the oblique to approximately a parallel with the roller axis, to adapt it to properly press upon the end of the tube while the edge of the latter is turned more and more toward the flue sheet.

It will be observed that in the rotation of the body, 3, the rim, 7 does not bear upon the flue sheet nor upon the end of the tube; but only said beading rollers bear against the end of the tube, while the expansion rollers bear against the interior of the tube, leaving the body, 3, entirely without contact against either the tube or the flue sheet.

Any desired number of beading rollers may be used; but a small number is preferable because the pressure by each roller upon the flange is then greater and better adapted for bending the tube. Hence the drawings show only two such rollers.

From the foregoing it will be seen that the two portions of the work, the expanding and the beading, are done simultaneously, whereby time is saved. And, although the operation is thus duplex, it requires less power than is required in analogous tools in which a rim, similar to the rim, 7, of my construction, bears upon the flue sheet and rotates while bearing against said sheet. The friction involved in such rotation is absent in my construction, there being, as above described, no contact between the rim, 7, and the flue sheet, and the beading rollers serving as anti-friction rollers for the rotation of the body, 3.

I claim as my invention:

1. In a device of the nature described, the combination of a tapering mandrel, a tubu lar body surrounding said mandrel and having oblique slots, expansion rollers located in said slots and bearing upon said mandrel and projecting outside of said slots, and beading rollers located transversely to the mandrel axis whereby the expansion rollers in their operation simultaneously feed the beading rollers to their work;

2. In a device of the nature described, the combination of a tapering mandrel, a tubular body surrounding said mandrel and having oblique slots and a rim, expansion rollers located in said slots and bearing upon said mandrel and projecting outside of said slots, and beading rollers located between said rim and said body whereby the expansion rollers in their operation simultaneously feed the beading rollers to their work.

In testimony whereof I have signed my name, in presence of two witnesses, this 19th day of March, in the year one thousand nine hundred and nine.

JOSEPH L. DIDIER.

Vitnesses Cyrus KEHR, C. A. Monsn. 

